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61.
The α subunit of a GTP-blndlng protein, Go, was investigated in pulmonary neuroendocrine neoplasms and fetal tissues of the lung by an immunohistochemlcal method. Positive immunostaining for the α subunit of Go (Goα) was found predominantly on the cell membrane and found occasionally in the cytoplasm. Typical carcinoids were all positively stained (9/9), and small cell carcinoma showed weaker and less frequent staining (5 positive cases in 10). Atypical carcinoids were variously stained (3/4). The tendency for obvious neuroendocrine differentiation to be immunohistochemically determined in typical carcinoids and not in small cell carcinoma is also true of staining for neuron specific enolase (NSE), chromogranin A (CG-A) and synaptophysin. In the lung, Goα-immunostaining was positive not only in nerve tissues but also in the airway epithelium. In the fetal lung, serial sections immunostained for NSE, CG-A and Goα confirmed that Goα-immunoreactive cells belong to the neuroendocrine cell population. The biological significance of Goα is unclear in normal and neoplastic lung tissues, but Goα is a useful marker of neuroendocrine cells and neoplasms of the lung.  相似文献   
62.
RAG1/GFP knockin mice were exploited to isolate and characterize fetal lymphoid progenitors. CD11b and IL-7Ralpha are expressed in a developmental stage-dependent fashion, revealing how substantial numbers of early lymphoid progenitors were discarded or neglected in previous studies. The myeloerythroid potential of fetal progenitors in clonal assays declined in synchrony with activation of the RAG1 locus but was not completely extinguished. Lymphoid differentiation corresponded to patterns of gene expression previously found for adult marrow, but no fraction of fetal liver was enriched with respect to B + T progenitors. Also, unlike adults, fetal lymphoid progenitors transiently expressed endothelial cell markers. These findings help to reconcile discrepancies in previous reports and suggest that the fetal immune system arises via unique mechanisms.  相似文献   
63.
青蒿琥酯对曼氏血吸虫雌虫生殖作用的影响   总被引:2,自引:0,他引:2  
目的 :通过观察青蒿琥酯对曼氏血吸虫雌虫产卵的影响 ,分析药物的抗生殖作用。方法 :小鼠尾部接触感染曼氏血吸虫尾蚴后口服不同剂量青蒿琥酯 ,灌流后收集虫体 ,记数。解剖小鼠取出肝、肠 ,组织溶解后计数虫卵 ,分析药物作用后雌虫平均产卵量的变化 ;收集无损虫体进行体外培养 ,计数雌虫体外产卵并观察虫卵形态。结果 :在 30 0mg kg和 5 0 0mg kg给药组小鼠的肝、肠中未查到虫卵 ,10 0mg kg给药组小鼠的雌虫平均产卵量与对照组存在极显著性差异 ;体外培养结果中 ,30 0mg kg和 5 0 0mg kg给药组的虫体未见产卵 ,10 0mg kg给药组雌虫平均产卵量与对照组存在显著差异。显微观察发现 10 0mg kg给药组雌虫体外培养所产的虫卵多外附泡状物 ,侧棘受损 ,虫卵结构异常。结论 :青蒿琥酯能降低或完全抑制存活雌虫的平均产卵量、导致雌虫异常卵的产生 ,具有抗曼氏血吸虫雌虫生殖的作用 ,能有效预防曼氏血吸虫病的发生和传播  相似文献   
64.
Posterior polymorphous corneal dystrophy (PPCD) is an autosomal dominant disorder characterized by corneal endothelial abnormalities, which can lead to blindness due to loss of corneal transparency and sometimes glaucoma. We mapped a new locus responsible for PPCD in a family in which we excluded the previously reported PPCD locus on 20q11, and the region containing COL8A2 on chromosome 1. Results of a 317-marker genome scan provided significant evidence of linkage of PPCD to markers on chromosome 10, with single-point LOD scores of 2.63, 1.63, and 3.19 for markers D10S208 (at (circumflex)theta = 0.03), D10S1780 (at (circumflex)theta = 0.00), and D10S578 (at (circumflex)theta = 0.06). A maximum multi-point LOD score of 4.35 was found at marker D10S1780. Affected family members shared a haplotype in an 8.55 cM critical interval that was bounded by markers D10S213 and D10S578. Our finding of another PPCD locus, PPCD3, on chromosome 10 indicates that PPCD is genetically heterogeneous. Guttae, a common corneal finding sometimes observed along with PPCD, were found among both affected and unaffected members of the proband's sib ship, but were absent in the younger generations of the family. Evaluation of phenotypic differences between family members sharing the same affected haplotype raises questions about whether differences in disease severity, including differences in response to surgical interventions, could be due to genetic background or other factors independent of the PPCD3 locus.  相似文献   
65.
The influence of intestinal microflora and aging on the lipid metabolism in germfree (GF) and conventional (CV) rats, 8 and 40 weeks old, was investigated. Serum cholesterol at the age of 8 and 40 weeks and serum triglyceride (TG) at the age of 40 weeks was higher in GF than in CV rats. Serum cholesterol decreased and serum TG and corticosterone tended to increase in both GF and CV rats with aging. In the rats 40 weeks of age, lipase activity of the pancreas and the duodenal, jejunal, and colorectal contents in GF rats increased, but that of the ileal and cecal contents in GF and CV rats decreased. Intestinal microflora tended to depress the age-related increase of serum TG and lipase activity of the pancreas and the duodenal and jejunal contents Lipoprotein lipase (LPL) and hormone-sensitive lipase (HSL) activities of the epididymal adipose tissue were higher in CV than in GF rats at both 8 and 40 weeks of age. The LPL activity increased and the HSL activity decreased in both GF and CV rats with aging. The concentration of cholesterol increased and that of bile acids decreased in the cecal contents of 40-week-old GF rats.  相似文献   
66.
Five cases of primary sclerosing scrotal lipogranuloma were examined histologically and immunohistochemically. Every case lacked a history of injection or trauma, and revealed Common histologicat features; a typical granuloma composed of epithelioid cells and multinucleated giant cells, and inflammatory infiltrates of eosinophils, lymphocytes and macrophageimonocytes in the interstitium. lmmunahistochemistry disclosed the epithelioid cells and multinuclaated giant cells of the granuloma to be monocytetr in nature, as bath types of cells were positive for lyso-yme, α-1-antltrypin, α-1-antichymotrypsin, and KP-1. In the interstitium, KP-1 positive monocytes, L-26 positive B lymphocytes, UCHL-1 positive T lymphocytes and 5–100 protein positive Langerhans-like cells were frequently found. 5100 protein positive cells could not be detected in the granuloma. Primary sclerosing lipogranuloma of the scrotum, therefore, is a peculiar inflammation characterized by granulomas consisting of monocytes and marked tissue eosinophilia of unknown etiology.  相似文献   
67.
A Ph1 chromosome-negative chronic myelogenous leukemia (CML) with t(7;11)(p15;p15) in a 6-year-old girl is reported. Three cases of 7;11 translocation have been reported so far. The patients concerned were between 37 and 72 years of age; 2 of them had CML and the other had acute myelomonocytic leukemia. Data from these 4 cases suggest that the 7;11 chromosome translocation may be related to a subgroup of Ph1-negative CML, specifically to one that may easily proceed to blast phase, or to "subacute" myelogenous leukemia. The present case demonstrates that CML with this chromosome abnormality is not restricted to adults but also affects children. The t(1;11)(q21 or 23;p15) reported in another case with Ph1-negative CML may be a variant of this translocation.  相似文献   
68.
Obstructive jaundice was produced in rats by ligation and transection of bile duct outside the liver; the control group underwent laparotomy alone. Pancreatic wet weight, amylase, lipase, protein, DNA, RNA, RNA/DNA ratio, and weight/100 g DNA were significantly increased in jaundiced rats when compared to control rats. Histologic evaluation of pancreatic tissue obtained from jaundiced rats revealed the appearance of large or multiple nuclei in pancreatic acinar cells. Basal plasma levels of immunoreactive CCK were significantly increased in haundiced rats at two weeks and four weeks but, when compared to the levels obtained in laparotomized controls at those time intervals, CCK levels were not significantly different. In jaundiced rats, plasma immunoreactive gastrin was found to be significantly decreased at two and four weeks. Plasma gastrin levels were also found significantly decreased when the jaundiced group was compared with laparotomized control group. The results suggest that obstructive jaundice induced enlargement of the pancreas, probably due to hyperplasia and hypertrophy of pancreatic cells. Whether or not this phenomenon is related to changes in gastrin and CCK is not known.This work was presented in part at the 36th Kinki Section Meeting of Japanese Gastroenterological Association (January 1982) in Osaka, Japan; at the Annual Meeting of the Japanese Pancreatic Association (March 1982) in Hiroshima, Japan; and at the American Gastroenterological Association (May 1983) in Washington, D.C.; and appeared in abstract form inGastroenterology 84: 1095, 1983.  相似文献   
69.
Recent reports have described midterm natural courses of osteochondral lesion of the talus (OLT) and lack of progression of ankle osteoarthritis (OA) in adult patients. The relationship between the OLT managed with nonoperative treatment and development of OA in children remains unknown. We report the long-term course of medial OLT in a 12-year-old female who was treated nonoperatively for 10 years. Radiographically, no osteoarthritic changes were observed at the first examination. She initially returned to her basketball club after nonoperative treatment. Although daily activities were not restricted, limitation of recreational activities began to appear at 4 years of follow-up. Subsequently, plain radiographs revealed bone absorption around the osteochondral fragment and osteophyte formation at the medial gutter, then ankle OA was advanced at the final follow-up.  相似文献   
70.
Summary Defibrotide is known to enhance prostacyclin (PGI2) release from the vascular endothelium. We investigated the vasoactive effects of defibrotide in isolated rat hearts perfused at constant flow subjected to ischaemia and reperfusion. Defibrotide at 10–7 or 100 g/ml did not exert any direct vasoactive effect on normal rats hearts. However, ischaemia and reperfusion resulted in an impaired vasodilation to acetylcholine, an endothelium-dependent vasodilator. In contrast, the vasodilator response to the endothelium-independent dilator, nitroglycerin, was unaffected. Defibrotide, at 10–7 or 100 g/ml, markedly restored the vasodilation to acetylcholine 10–7 nmol/l to 1 mol/l (P < 0.01) without influencing the vasodilator response to nitroglycerin (2 to 200 g/1). Haemoglobin (150 nmol/l) inhibited the dilation to acetylcholine in response to defibrotide. However, no evidence of (PGI2) release was observed with acetylcholine-induced vasodilation in the presence or absence of defibrotide. Additionally, 10–100 g/ml of defibrotide did not significantly decrease superoxide radicals generated by a xanthine-xanthine oxidase synthetic system under conditions in which superoxide dismutase was effective. Thus, defibrotide appears to exert an endothelium-protective effect preserving endothelium-derived relaxing factor (EDRF) without directly scavenging free signals.Supported in part by Research Grant No. HL-25575 from the National Heart, Lung and Blood Institute of the NIH Send offprint requests to A. M. Lefer at the above address  相似文献   
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